Rectilinear Steiner Minimum Tree Slot

This slot is focused on the Rectilinear Steiner Minimum Tree (RSMT)
problem:

Problem

Given a set P of n points, find a set S
of Steiner points such that the Minimum Spanning Tree (MST)
over P + S has minimum cost.

The RSMT problem is NP-hard. This page presents an exact algorithm (GeoSteiner),
two quadratic heuristics (BOI and
BI1S), a O(nlog2n) heuristic (batched greedy),
and a O(n log n) Rectilinear
Minimum Spanning Tree (RMST)
code.
The RMST is never more than 50% longer
than RSMT, and on the average comes within 12% of the RSMT. The BI1S,
BOI, and batched greedy heuristics come on the average within 0.5-0.7% of the
optimum RSMT.